This chapter covers the following topics:
- DNS
- HTTP/HTTPS
- FTP
- Instant Messaging
- Application Evaluation
I don't want to insist on it, Dave, but I am incapable of making an error.
Arthur C. Clarke, 2001: A Space Odyssey, 1968
The Answer to the Great Question . . . Of Life, the Universe and Everything . . . Is . . . Forty-two.
Douglas Adams, The Hitch Hiker's Guide to the Galaxy, 1979
Although this book will certainly not go into great detail on application security, in certain cases application security relies on the network for its overall security strategy. This chapter presents best practices for the deployment of e-mail, DNS, HTTP/HTTPS, and FTP. A short discussion on instant messaging (IM) and application security evaluations is also provided. The emphasis in this chapter is on network placement and filtering guidelines, not application hardening. In addition to these placement guidelines, be sure to follow the hardening steps in Chapter 5, "Device Hardening," and deploy host security controls as discussed in Chapter 4, "Network Security Technologies." Specific application security recommendations for these protocols can be found online or in any number of books, some of which are referenced in this chapter.
NOTE
The examples used in this chapter are focused on the firewall. The deployment of intrusion detection systems (IDS) and other security technologies is expected but not included because such technologies don't generally impact the logical topology of the network. Similar designs with all security components included (and multiple applications) are included in Part 3 of this book.
Part I. Network Security Foundations
Network Security Axioms
Security Policy and Operations Life Cycle
Secure Networking Threats
Network Security Technologies
Part II. Designing Secure Networks
Device Hardening
General Design Considerations
Network Security Platform Options and Best Deployment Practices
Common Application Design Considerations
Identity Design Considerations
IPsec VPN Design Considerations
Supporting-Technology Design Considerations
Designing Your Security System
Part III. Secure Network Designs
Edge Security Design
Campus Security Design
Teleworker Security Design
Part IV. Network Management, Case Studies, and Conclusions
Secure Network Management and Network Security Management
Case Studies
Conclusions
References
Appendix A. Glossary of Terms
Appendix B. Answers to Applied Knowledge Questions
Appendix C. Sample Security Policies
INFOSEC Acceptable Use Policy
Password Policy
Guidelines on Antivirus Process
Index